George Gehrels

The Arizona LaserChron Center is a research facility at the University of Arizona that uses laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to determine U-Pb ages of detrital zircon and other accessory minerals. It serves as a national shared facility, allowing geoscientists from institutions across the country to analyze mineral samples for provenance and tectonic studies.

Detrital zircon dating involves measuring uranium-lead isotope ratios in individual zircon grains eroded from source rocks and deposited in sedimentary basins, providing the crystallization ages of those source rocks. This technique is fundamental for reconstructing the provenance of sedimentary units, understanding ancient mountain-building events, and mapping the assembly and breakup of continents over geological time.

A laser vaporizes a microscopic spot on a mineral grain, and the resulting aerosol is carried into a mass spectrometer that measures the relative abundances of uranium and lead isotopes. The ratio of these isotopes yields the crystallization age of the mineral, with precision sufficient to distinguish geological events separated by only a few million years.

Yes, the Arizona LaserChron Center is funded as a national shared facility, meaning researchers from other universities and institutions can submit samples for analysis. Gehrels designed the center specifically to serve the broader geoscience community, and it has supported thousands of research projects from institutions worldwide since its establishment.